QA Engineer - Ostium Labs - Miami, FL

Ostium is on a simple mission: make it possible for anyone with a digital wallet to trade stocks, commodities, currencies, and crypto with full transparency. No brokers, no freezes, no hidden spreads. We're replacing the opaque, offshore brokerage model with a transparent, permissionless trading stack built onchain. Every trade, deposit, and withdrawal is verifiable through open, auditable code. We've raised $27.9M+ from General Catalyst, Jump, LocalGlobe, Susquehanna (SIG), GSR, Alliance DAO, Soma Capital, Balaji Srinivasan, Meltem Demirors, and others.

QA Engineer (Remote / Full-Time)We're hiring a QA engineer (2-4 years experience) who understands DeFi. You'll own quality across our web and mobile frontends, not just running test cases, but thinking like a user who has real money on the line. You need to understand how perpetual trading works, what leverage means, how wallets connect, how transactions flow and where all of that can break.

ResponsibilitiesOwn quality across web and mobile frontends

Think like a real user with money on the line - hunt for edge cases, broken flows, and UX friction

Write and maintain automated test suites for the web app (Cypress, Playwright, or similar)

Test DeFi-specific flows - wallet connections, approvals, order types, transaction states, network switching

File detailed, actionable bug reports with reproduction steps engineers can immediately act on

Use browser dev tools and logs to investigate issues beyond surface-level symptoms

Work with engineering to verify fixes, catch regressions, and validate releases before they ship

Help build and improve CI-integrated test pipelines over time

RequirementsSolid experience testing web and mobile applications.

Familiar with DeFi primitives like wallets, approvals, order types, on-chain vs off-chain flows, network switching, transaction states.

You should be able to look at a trading interface and intuitively know what edge cases to hunt for.

Experience with automation te